We thought long and hard about how many amps current to run new 2X at, did some experiments, and finally decided at 4.5. Its not the max for an XML2-U4 but it's extreme output in the 2X and still stable.
Q - your 5 amp 2X must be running at 400k lux or a tad more - that's a helluva lot of light esp in the 0-200m range. Sunglasses I think.....
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